Question

The electron configuration $1s^{2}2s^2{p}^{6}3s^2{p}^{6}4s^{2}3d^7$ represents an atom of the element

• A. $Br$
• B. $Co$
• C. $Cd$
• D. $Ga$
• E. $Mg$

Answer 1

The correct option is B $Co$

The given electronic configuration is of ${}_{27}Co$.